Azole N-oxides. Part IV. Deoxygenation and side-chain substitution reactions of some 1-methoxypyrazole 2-oxides
Abstract
1-Methoxypyrazole 2-oxides undergo the normal acyloxy migration reaction of N-oxides with acetic anhydride to give 3- and 5-acetoxymethylpyrazoles. With phosphorus trichloride and with benzoyl chloride abnormal reactions were observed, leading to 3-chloromethylpyrazoles, in some cases accompanied by simple deoxygenation of the N-oxide.